Domestic oven with air cooling system



March 21, 1967 e. A. SCOTT ETAL 3,310,046

DOMESTIC OVEN WITH AIR COOLING SYSTEM 5 Sheets-Sheet 1 Filed March 2, 1965 INVENTORS GEORGE A. scoTT YZJAMES K. NEWELL. :m B M02 m PIC-3.2

THE \R ATTORNEY March 21, 1967 G. A. SCOTT ETAL 3,310,046

DOMESTIC OVEN WITH AIR COOLING SYSTEM Filed March 2, 1955 I 3 Sheets-Sheet 2 INVENTORS GEORGE A. SCOTT M Mwm THEIR ATTORNEY $ITAMES K. NEWELL IR,

March 21, 1967 G. A. sco'r'r ETAL 3,310,045

DOMESTIC OVEN WITH AIR COOLING SYSTEM Filed March 2, 1965 3 Sheets-Sheet 5 GEORGE A. SCOTT 1; JAMES K. NEWELL TF2.

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THEIR ATTORNEY United States Patent 3,310,046 DOMESTIC OVEN WITH AIR COOLING SYSTEM George A. Scott, Jeffersontown, and James K. Newell,

Jr., Louisville, Ky., assignors to General Electric Company, a corporation of New York Filed Mar. 2, 1965, Ser. No. 436,436 14 Claims. (Cl. 12621) The present invention relates to a domestic baking oven and particularly a built-in wall oven that is provided with an air cooling system to restrict the maximum external temperatures of the oven as Well as to increase the useful life of the oven control components.

This invention was conceived during the development of a built-in wall oven design that incorporates a high temperature self-cleaning oven cycle using the principle of pyrolysis for removing the food soil and grease spatter from the inner wall surfaces of the oven liner. The basic principles of a self-cleaning oven are best described and claimed in the recent patent of Bohdan Hurko No.

3,121,158, which is assigned to the General Electric Company, the assignee of the present invention. Such a selfcleaning oven cycle has a maximum oven temperature somewhere between about 750 F. and 950 P. so as to decompose all food soil and grease spatter lodged on the oven liner walls by degrading the soil into gaseous products which are then passed through an oxidation unit or smoke eliminator which further decomposes the gases before they are returned to the kitchen atmosphere.

A special temperature problem arises when such high temperatures are utilized in an oven that is built into a wall since the oven is totally enclosed except for the front portion thereof which includes the oven door and the overlying control panel. Means must be provided to restrict the maximum operating temperatures of the outer surfaces of the oven cabinet as well as to prevent the oven control components from becoming overheated thereby shortening the useful life thereof.

The principal object of the present invention is to provide a high temperature domestic oven and particularly a built-in wall oven with an air cooling system to restrict the maximum operating temperatures of the outer surface of the oven as well as to protect the oven control components from excessive temperatures.

A further object of the present invention is to provide a built-in wall oven with a forced draft cooling system for preventing hot spots in the outer surface of the oven cabinet as well as to guard the oven control components from being exposed to excessive temperatures.

A still further object of the present invention is to provide a built-in Wall oven with an air cooling system having a plenum chamber encompassing the control panel, and air openings beneath the panel to constitute a thermal break in the heat path to the oven control components.

The present invention, in accordance with one form thereof, is embodied in a domestic oven either gas or electric having inner walls and an access forming an oven cooking cavity. An oven control panel is positioned above the door and air passages are formed around the outside of the oven cavity. Air openings are formed adjacent the bottom edge of the door as well as along at least one side edge of the door, and other openings are formed beneath the control panel. A blower means is provided for circulating relatively cool room air through the air passages. Other refinements include a transverse partition in which a blower means is mounted to form with the control panel a plenum chamber near the front top portion of the oven. The preferred embodiment has the air entering at the bottom and along at least one side of the oven door, while the cooling air returns to the kitchen atmosphere through the air openings beneath the control panel so as to form a thermal break in the heat ice path between the oven cavity and the control panel. Other modifications would rearrange the control panel to be along one side or beneath the oven door. Also, the direction of air flow could be reversed to flow from top to bottom.

Our invention will be better understood from the following description taken in conjunction with the accompanying drawings and its scope will be pointed out in appended claims.

FIGURE 1 is a right side elevational view of an electric oven for use as a built-in wall oven with parts broken away and some in cross-section to show an air cooling system having means for removing some of the heat from the oven liner walls as well as for restricting the degree of temperature to which the oven control components are exposed.

FIGURE 2 is a fragmentary cross-sectional plan view at the back of the oven taken on the line 2-2 of FIG- URE 1 to show the isolation means or shroud for preventing smoke leakage from around the oven components that are mounted in the back wall of the oven liner.

FIGURE 3 is a rear elevational view of the oven of FIGURE 1 with parts broken away along the left side of the oven to show the air chamber between the inner oven cabinet and the outer oven cabinet as well as the nature of the oven components mounted through the back wall of the oven liner.

, FIGURE 4 is a front elevational view of the built-in wall oven of FIGURE 1 with the box-like oven liner and the oven heating elements shown in dotted line.

' FIGURE 5 is an isometric view of both the transverse partition and the bottom wall forming the plenum chamber that lies behind the control panel, as well as showing the blower means mounted through the partition at the right side thereof.

Turning now to a consideration of the drawings, and in particular to FIGURE 1, there is shown a right side elevational view of a built-in wall oven 10 with parts broken away to show the oven cavity 11 formed by a box-like oven liner 12 with a front opening that is adapted to be closed by a hinged oven door 13. The particular oven shown is an electric oven having a lower baking element 14 and an upper broiling element 15 as is conventional in this art. An additional heating means is used in the form of a perimeter or mullion heater 17 adjacent the front of the oven and encircling the oven liner. This heater 17 serves to compensate for heat lost through and around the oven door 13, as well as for obtaining generally uniform temperatures throughout the oven cavity during the high temperature heat cleaning cycle, as was mentioned heretofore.

Due to the high temperatures encountered in this oven, an extra amount or thickness of thermal insulation 19 such as fiberglass or the like is assembled around the outside of the oven liner 12 for retaining as much as possible of the oven heat within the oven cavity. In a similar manner, the oven door 13 is heavily insulated as compared with a standard oven door. A special high temperature door gasket 21 is carried by the door and adapted to be compressed against the front peripheral edge of the oven liner 12 for both sealing the oven cavity when the door is closed as well as restricting the amount of air that enters the cavity during the heat cleaning cycle so as to control the rate of decomposition of the food soil. Moreover, there is an oven door latching mechanism 22, diagrammatically shown as only a latch handle, for locking the oven door 13 in the closed position and preventing the unlocking thereof while the oven temperature is above a predetermined maximum cooking temperature of about 600 F. Such a door latching therefore, it is neither shown nor described in detail as many different types of door latching mechanisms may be used Without departing from the scope of the present invention.

In order to hold the fibrous oven insulation 19 in its proper place, an insulation guard or inner oven cabinet 24 surrounds the insulation. This is especially true adjacent the bottom of the oven and along the vertical walls, that is, the two side walls and the back wall. This insulation guard is not as necessary at the top wall because of the natural force of gravity that acts upon the fibrous insulation. Hence, it will be noted in FIGURE 1, that toward the back of the oven the insulation 19 over the top wall of the oven liner is not covered by a sheet metal panel or insulation guard. Also, it will be understood by those skilled in this art that in actual practice the insulation guard 24 or inner oven cabinet is a box-like oven structure into which the insulation 19 is assembled prior to the insertion of the oven liner 12 through the front wall of an outer cabinet 26 of the oven. This outer oven cabinet 26 surrounds the insulation guard 24 and is spaced outwardly therefrom to provide an air cooling chamber 27 therebetween that completely surrounds the insulated oven liner, as is best seen in FIGURES 1-3. Also, in actual practice it is more practical to assemble these various oven elements from the outside in, rather than from the inside out, as has been described above.

At the front of the oven beneath the oven door 13 is an open grill work 29 of elongated shape that extends from side to side thereof and serves as a primary air inlet means for the air space or cooling chamber 27. Additional air inlet openings are formed in the outer oven cabinet 26 at the two sides of the oven door opening adjacent the top thereof by forming corrugations 30 in the front edge of the side wall as is best seen in FIGURE 1. These corrugations 30 are formed by slitting the sheet metal sides along vertically spaced lines 31 and pressing in tabs 28 which receive fastening screws 36. Thus the air may pass through the slit openings 31 as well as under the free front edge of the side wall between the slit openings. Moreover, the oven has a front frame 16 best shown in FIGURES 1 and 3 which has a back edge that is adapted to seat against the front surface of the wall in which the oven is mounted. There is an air gap provided by such frame 16 to supply air to the openings formed by the corrugations 30.

A control panel 32 is positioned above the oven door 13, and it contains the various electrical oven controls indicated broadly as element 33 and including such devices as an oven selector switch, an oven thermostat, a clocktimer, meat thermometer temperature indicator, and perhaps a convenience outlet as is more or less conventional in this art. Beneath the control panel 32 is shown the beforementioned handle 22 for operating the door latching mechanism. As is best seen in FIGURE 4, this handle extends through a suitable elongated slot 23 in an open grillwork 34 that serves as an air outlet means for the air cooling chamber 27. Behind the grill work 34 is a second grill 35 of an alternating design which serves to obstruct the view into the air chamber 27 behind the control panel 32 so as not to be able to see any of the oven insulation or lead wires connected to the oven control. Another advantage in using such structure is that there is no straight line-of-sight openings which might permit electrical arcing to escape in the event of an electrical failure of one of the control components 33.

A transverse partition 37 is positioned in the cooling chamber 27 above the oven cavity 11 to form with the control panel 32 a plenum chamber 40 that, of course, encompasses the control panel. Mounted through the transverse partition 37 is a motor operated fan 38 which creates a negative pressure at the back of the oven for drawing room air into the cooling chamber 27 through the air inlet openings 29 and around the corrugations 30 until the air sweeps over the insulated oven liner and then is drawn through the fan 38 into the plenum chamber 40.

A limited cyclone action takes place in the plenum chamber to distribute the cooling air throughout the plenum chamber before it is discharged through the outlet openings in the grills 34 and 35. These outlet openings form a thermal break in the heat path between the oven cavity 11 and the oven controls 33. Moreover, there is a spreader vane 41 mounted on the bottom wall 42 of the plenum chamber and partially extending in front of the fan unit 38 so as to deflect some of the air flow toward the side of the plenum chamber remote from the fan.

Notice that a damper 44 is hinged in front of the fan 38 to serve as both a closure and a tell-tale that cooperates with an interlock switch (not shown) that is series connected in the power circuit to the oven heating elements. Hence, during the high temperature heat cleaning cycle, the heating elements 14 and 15 cannot be energized unless the fan 38 is ope-rating and the damper is blown open. This provides a means to insure that the air cooling system is operational during the heat cleaning cycle. An overcenter counterweight 46 is shown combined with the top of the damper 44 to assist by use of gravity in closing the damper when the fan is de-energized. The bottom wall 42 of the plenum chamber is of irregular shape and extends completely from one side wall to the other of the outer oven cabinet 26 so that all air entering the cooling chamber 27 must first pass up and to the rear of the oven and then move through the fan 38 before it may reach the plenum chamber 40.

The oven 10 is also supplied with an oven vent 48 in the top wall of the oven liner 12 for exhausting hot oven gases therethrough. Connected to the oven vent 48 is a catalytic oxidation unit 49 which receives the oven gases and oxidizes them before they are returned to the kitchen through a horizontal duct work 50 that is directed toward the front of the oven and discharges through an elongated nozzle 51. This oxidation unit 49 is of the general type described and claimed in the patent of Stanley B. Welch No. 3,900,483 which is assigned to the General Electric Company, assignee of the present invention. This unit is not shown in greater detail because it does not form part of the present invention.

Notice that the bottom wall 42 of the plenum chamber 46 overlies the oxidation unit 49 and duct work 50, so that these elements are not present in the plenum chamber 40. In effect, the bottom wall 42 serves as a heat shield to restrict the radiation of heat to the oven control components 33. However, it is well to direct some of the cooling air over the duct work 50. This is the reason that the fan 38 is aligned with the oxidation unit. An air slot 54 is formed through the bottom wall 42 of the plenum chamber for receiving a blast of cooling air that is directed at high velocity over the duct 50 and finally around the nozzle 51 and out of the grill work 34 beneath the control panel 32. Thus, the relatively cool air mixes with the exhaust from the duct to reduce the oven exhaust temperature to a safe level. It is best not to cool the oxidation unit because the higher its temperature the higher its operating efiiciency.

The above description covers the main inventive contributions that are being claimed herein, but additional explanation will be made of the design of the back portion of the oven in order to improve the understanding of the drawings and the invention. As is standard practice in this art, several oven components are mounted through the back wall of the oven liner 12 as is best seen in FIGURES 1-3. First, there is an oven lamp 57 with its heat shielding lens 58 and external larnpholder 59. Then, of course, there are the terminal ends 60, 61 and 62 of the bake element 14, broil element 15, and mullion heater 17 respectively. Usually, small clearances are provided around these oven components in the back wall of the oven liner 12 as well as in the insulation guard 24 in order to allow for both expansion and contraction of the different materials that have dissimilar coeflicients of thermal expansion. These clearances are also important for both ease of assembly and the necessity for providing engineering tolerances to compensate for the attrition of the forming tools used in making the oven components, the oven liner and insulation guard.

When the walls of the oven liner are heavily coated with food soil and grease spatter and the high temperature heat-cleaning cycle is initiated some smoking may take place in the oven cavity. However, when the fan 38 is energized to create a negative pressure in the air space 27 upstream of the fan it may happen that smoke is drawn through the clearance openings around the oven components in the back wall of the oven liner due to the pressure differential existing between the oven cavity 11 and the air cooling chamber 27. Since the cooling air does not pass through the oxidation unit 49, this smoke that enters the cooling chamber 27 may be discharged into the kitchen through the air outlet 34. This would be highly objectionable to the housewife and means would have to be provided for preventing this possibility.

Looking at the back portion of the oven in FIGURE 3, a single four-sided shroud 64 encircles the several oven components 59-62, and the shroud extends between the insulation guard 24 and the outer oven cabinet 26, as is best seen in FIGURE 2. The back wall of the outer oven cabinet 26 is removable so as to permit access to the oven components for mounting and wiring purposes. Thus, the space encompassed by the shroud 64 may be considered as a wiring chamber 66 that is separate or isolated from the cooling chamber 27. This wiring chamber is open to the atmosphere through the louvers 67. This smoke leakage prevention means; namely, the shroud 64 is fully described and claimed in the copending application of George A. Scott, Ser. No. 436,615, which was filed concurrently herewith and entitled Domestic Oven With Smoke Leakage Prevention. It is also assigned to the General Electric Company, the assignee of the present invention.

Modifications of this invention will occur to those skilled in this art, therefore, it is to be understood that this invention is not limited to the particular embodiments disclosed but that it is intended to cover all modifications which are within the true spirit and scope of this invention as claimed.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. A domestic built-in wall oven comprising inner walls defining an oven cooking cavity, one wall having an access opening and a door for closing said opening, heating means for cooking foods placed within the oven cavity, thermal insulating means surrounding the walls of the oven cavity, an outer oven cabinet surrounding the insulated oven walls but outwardly spaced therefrom to form a cooling air chamber therebetween, the air chamber having air inlet openings and air outlet openings, blower means within the oven cabinet for forcing relatively cool air through the air chamber so as to dissipate some of the heat that is present in the inner oven walls, and an oven control panel located above the oven door, the air outlet openings being disposed between the oven door and control panel to provide a thermal break in the heat path between the oven cavity and the oven control panel, the air inlet openings being located beneath the oven door as well as in the outer oven cabinet at the opposite sides of the door near the top thereof.

2. A domestic built-in wall oven comprising oven liner walls forming an oven cavity where one wall of the cavity includes a door for gaining access thereto, heating means for cooking foods placed within the oven cavity, an outer oven cabinet surrounding the oven liner walls and forming a cooling air chamber therebetween, the air chamber having an elongated air inlet opening located beneath the oven door, a blower means located in the air chamber above the oven cavity, and an oven control panel located above the oven door and substantially in the plane thereof, and an elongated air outlet opening disposed between the oven door and the oven control panel to provide a thermal break in the heat path between the oven cavity and the oven control panel, a transevrse wall in which the blower means is mounted to form a plenum chamber downstream of the blower means, the plenum chamber having a bottom wall that is closed to the portion of the cooling air chamber at the side walls of the oven cavity so that the main current of ambient air is first drawn from the front of the oven toward the back thereof in an upward direction and then passes through the blower means into the plenum chamber from which it is exhausted through the air outlet opening.

3. A domestic built-in wall oven comprising inner walls defining an oven cooking cavity, one wall having an access opening and a door for closing said opening, heating means for cooking foods placed within the oven cavity, an outer oven cabinet surrounding the oven walls but outwardly spaced therefrom to form a cooling air chamber therebetween, an oven control panel located above the oven door, control components mounted on the control panel, the back surface of the control panel being exposed to the cooling air chamber, an oven exhaust vent in the top wall forming the upper portion of the oven cavity, and duct means connected to the exhaust vent and extending to the front of the oven structure to separate the hot oven gases from the cooling air as well as dis charge said gases externally of the oven structure, the cooling air chamber having an air inlet means beneath the oven door and adjacent at least one side of the door near the oven exhaust vent, a transverse partition in the air cooling chamber above the oven cavity, blower means mounted through the partition generally in line with the oven exhaust vent to sweep cool air thereover, the said partition forming a plenum chamber with the control panel and the outer oven cabinet, and air distributing means cooperating with the blower means for spreading the air flow across the back portion of the control panel, and an air outlet means from the plenum chamber located between the top edge of the oven door and the bottom edge of the control panel to form a thermal break in the heat path between the oven cavity and the oven controls.

4. A domestic built-in wall oven comprising a boxlike oven liner and a front-opening oven door that is adapted to close with the oven liner and form an oven cooking cavity, heating means for the oven cavity for cooking foods placed therein, an oven control panel positioned above the door, an oven exhaust vent in the top Wall of the oven liner, and duct means connected to the exhaust vent and discharging from the front wall of the oven, a plenum chamber above the oven cavity, and a blower means combined with the plenum chamber, air inlet openings adjacent the bottom of the oven and being acted upon by the blower means for drawing relatively cool air around the outside of at least a portion of the oven cavity and delivering the cooling air into the plenum chamber, and an air outlet means from the plenum chamber located beneath the control panel to provide a thermal break in the heat path between the oven cavity and the oven control panel.

5. A domestic built-in wall oven comprising an insu-- lated oven liner and an access door for forming an oven cooking cavity, heating means furnished for the oven cavity for cooking foods placed therein, an oven control panel located above the access door, an oven exhaust vent in the top wall of the oven liner, and cooling means for the control panel comprising a plenum chamber positioned behind the control panel, the blower means combined with the plenum chamber for drawing relatively cool room air into the plenum chamber from around the insulated oven liner, the blower means being aligned with the oven exhaust vent so as to mix relatively cool air with the hot oven exhaust gases and thereby reduce the oven exhaust temperature, and air spreader means cooperating with the blower means for distributing the cooling air throughout the plenum chamber, and an air outlet means from the plenum chamber extending beneath the control panel to provide a thermal break in the heat path between the oven cavity and the oven control panel.

6. A built-in wall oven comprising a box-like oven liner having a front opening that is adapted to be closed by a movable access door, thermal insulation surrounding the oven liner, an oven control panel positioned above the access door, an inner oven cabinet surrounding the insulated oven liner, and an outer oven cabinet surrounding the inner oven cabinet but spaced outwardly therefrom to form an air cooling chamber therebetween, the cooling chamber above the oven liner also encompassing the control panel and having a transverse partition with a blower means mounted therein to form a plenum chamber behind the control panel, an oven exhaust vent located in the top wall of the oven liner and beneath the plenum chamber, duct means connected to the exhaust vent and extending to the outside of the oven structure, an opening in the bottom wall of the plenum chamber so that cooling air from the plenum chamber may sweep over the duct means.

7. A built-in wall oven comprising an insulated oven liner and an access door forming an oven cooking cavity, an oven control panel located directly above the access door, the oven cavity including heating means for cooking foods placed therein at normal temperatures between about 150 F. and 550 F., and heating means for accomplishing a pyrolytic self-cleaning oven cycle at temperatures between about 750 F. and 950 F., an oxidation unit positioned in the top wall of the oven liner adjacent a front corner thereof and serving as an oven exhaust vent means, duct means connected to the oxidation unit and extending through the front of the oven for exhausting to the atmosphere, an inner oven cabinet surrounding the insulated oven liner as an insulation guard, an outer oven cabinet surrounding the inner oven cabinet and spaced outwardly therefrom to form an air cooling chamber therebetween which also encompasses the control panel, air inlet means for the cooling chamber extending adjacent the bottom edge of the access door, air outlet means for the cooling chamber extending adjacent the top edge of the door so as to provide a thermal break in the heat path between the oven cavity and the oven control panel, and air circulating means within the cooling chamber for holding down the maximum external temperature of the outer oven cabinet as well as the maximum temperat-ure of the control panel.

'8. A built-in wall oven as recited in claim 7 wherein the air inlet means also includes openings in the outer oven cabinet adjacent the opposite sides of the access door.

9. A built-in wall oven as recited in claim 7 wherein the air circulation means is represented by a blower means mounted in a transverse partition in the cooling chamber above the oven cavity to form a plenum chamber between the partition and the control panel, the plenum chamber being closed to the cooling chamber except through the said blower means.

10. A built-in wall oven comprising an insulated oven liner and an access door for forming an oven cooking cavity, an oven control panel located directly above the access door, heating means for cooking foods placed within the oven cavity as well as for pyrolytically removing food soil from the inner surfaces of the oven cavity, an oven vent adjacent the top of the oven liner and including a catalytic oxidation unit for degrading the hot oven gases before they are returned to the atmosphere, and an inner oven cabinet surrounding the insulated oven liner, an outer oven cabinet enclosing the inner oven cabinet, air passages extending around the inner oven cabinet, air openings adjacent the lower edge of the access door and adjacent at least one side of the access door near the top thereof, air openings located adjacent the top of the oven door, and blower means for producing air flow through the said passages.

11. A built-in wall oven as recited in claim 10 where the oxidation unit has an exhaust duct directed to the outside of the oven, the blower means being aligned with the oxidation unit so as to sweep cool air over the exhaust duct to reduce the temperature of the exhaust gases to a safe limit.

12. A built-in wall oven as recited in claim 10 wherein the oxidation unit is provided with duct means directed to the front of the oven for discharge into the atmosphere, and heat shielding means over the unit and duct means to reduce the radiation of heat to the control panel, the blower means being aligned with the oxidation unit for sweeping some cool air under the shielding means and over the duct work to mix with the exhaust gases and reduce the temperature thereof.

13. A built-in Wall oven comprising an insulated oven liner and a front-opening access door forming an oven cooking cavity, an oven control panel located directly above the door, heating means for cooking food placed within the cavity as well as for pyrolytically removing food soil from the inner wall surfaces of the oven cavity, an oven vent opening in the top wall of the oven liner, a catalytic oxidation unit communicating with the oven vent for degrading the hot oven gases before they are returned to the atmosphere, duct means connected to the oxidation unit and directed to the front of the oven for discharge to the atmosphere, an inner oven cabinet surrounding the insulated oven liner including the oxidation unit and duct means, an outer oven cabinet surrounding the inner oven cabinet but spaced therefrom to form an air chamber therebetween which also encompasses the control panel, air inlet openings adjacent both the bottom edge of the door and along at least one side of the door, a transverse partition in the air chamber above the oven cavity to form a plenum chamber with the control panel, a blower means mounted through the partition, and air outlet openings from the plenum chamber located above the top edge of the door.

14. A domestic built-in Wall oven comprising oven liner walls forming an oven cavity where one wall of the cavity includes a door for gaining access thereto, heating means for cooking foods placed within the oven cavity, a blanket of thermal insulation surrounding the oven liner walls, an outer oven cabinet surrounding the said thermal insulation but spaced outwardly therefrom to form a cooling air chamber therebetween, the air chamber having a first air opening located adjacent one edge of the door, a control panel lying substantially in the same plane as the door but adjacent an opposite edge of the door, and a second air opening positioned between the said door and control panel and communicating With the said air chamber to provide a thermal break in the heat path between the oven cavity and the oven control panel, and air flow inducing means cooperating with the air chamber to draw room air through one of the said openings and sweep it throughout the air chamber and around the outside of the thermal insulation before the air is discharged from the air chamber through the other said opening.

References Cited by the Examiner UNITED STATES PATENTS 2,237,795 4/1941 Shroyer 12619 2,860,026 11/1958 Long.

3,032,028 5/ 1962 Pearce et a1. 126-21 3,051,158 8/1962 Kimberley 126-21 3,081,392 3/1963 Warner.

3,121,158 2/1964 Hurko 126-19 X 3,239,651 3/1966 Silberman 219411 X FREDERICK KETTERER, Primary Examiner. 

1. A DOMESTIC BUILT-IN WALL OVEN COMPRISING INNER WALLS DEFINING AN OVEN COOKING CAVITY, ONE WALL HAVING AN ACCESS OPENING AND A DOOR FOR CLOSING SAID OPENING, HEATING MEANS FOR COOKING FOODS PLACED WITHIN THE OVEN CAVITY, THERMAL INSULATING MEANS SURROUNDING THE WALLS OF THE OVEN CAVITY, AN OUTER OVEN CABINET SURROUNDING THE INSULATED OVEN WALLS BUT OUTWARDLY SPACED THEREFROM TO FORM A COOLING AIR CHAMBER THEREBETWEEN, THE AIR CHAMBER HAVING AIR INLET OPENINGS AND AIR OUTLET OPENINGS, BLOWER MEANS WITHIN THE OVEN CABINET FOR FORCING RELATIVELY COOL AIR THROUGH THE AIR CHAMBER SO AS TO DISSIPATE SOME OF THE HEAT THAT IS PRESENT IN THE INNER OVEN WALLS, AND AN OVEN CONTROL PANEL LOCATED ABOVE THE OVEN DOOR, THE AIR OUT- 